MoSync team has recently done an interesting comparison:
Which Mobile JavaScript framework is the best: jQuery Mobile, Sencha Touch, jQtouch, or Kendo UI?
http://www.codefessions.com/2012/04/mobile-javascript-frameworks-evaluation.html
http://www.codefessions.com/2012/04/which-mobile-javascript-framework-is.html
http://www.codefessions.com/2012/05/which-mobile-javascript-framework-is.html
jQueryMobile wins but huge boost in arm is because of licensing. I prefer jQueryMobile because I don't want someone(thing) else to write my markup, that way hacking becoming difficult (at least for me), however, I do have couple of HTML5 apps under my belt now, one each in jQM and Sencha Touch. Sencha Touch makes it smoother, very hard to learn though while jQM gets you started in a day, there are bug but you usually get around them because of amazing web community around this framework.
